Arguing that understanding what lies behind the apparent usability of direct manipulation style interfaces might not only help in building better interfaces, but can also draw attention to possible side effects, this paper uses examples from a prototype data manipulation system to pursue a characterization of direct manipulation interfaces as…

Based on systematic observations of five experienced online searchers, this model compares two searching styles: operationalist, which aims at optimal strategies to achieve precise retrieval and uses a large range of system capabilities, and conceptualist, which analyzes the request by seeking to fit it into a faceted structure. (13 references)…

In this study, automatic feedback techniques are applied to Boolean query statements in online information retrieval to generate improved query statements based on information contained in previously retrieved documents. Feedback operations are carried out using conventional Boolean logic and extended logic. Experimental output is included to…

Describes the TIS Intelligent Gateway, developed at the Lawrence Livermore National Laboratory, which uses an extensible meta-machine approach to accommodate unlimited target resources, and provides a universal user interface to simplify communications between the user and target resources. (6 references) (Author/CLB)

This examination of the effectiveness of various methods of cuing users to their location in a videotex information system used five different versions of an electronic edition of a college catalog: "simple" (no cues), "headers" (textual cues), "color" (color cues), "icons" (graphic cues), and…

Proposes a "Model of Querying" for users of office filing facilities and discusses its motivation, aspects, attributes, and advantages. A review of current information systems and attempts to combine information retrieval, artificial intelligence, and database management techniques leads to conclusion that no resultant system is adequate…

Evaluates and compares two recently proposed automatic methods for relevance feedback of Boolean queries (Dillon method, which uses probabilistic approach as basis, and disjunctive normal form method). Conclusions are drawn concerning the use of effective feedback methods in a Boolean query environment. Nineteen references are included. (EJS)

This paper describes a study that was undertaken at the University of Illinois at Urbana-Champaign to compare the databases selected by 75 inexperienced student online searchers aided by an existing gateway system--INFOMASTER, a version of EASYNET--with databases selected manually by four experienced searchers who were reference librarians from…